In planning, however, they are less popular, 1 partly due to the unsettled, strange relationship between probability and actions. In principle, actions are not part of standard probability theory, and understandably so: probabilities capture normal relationships in the world, while actions represent interventions that perturb those relationships. It is no wonder, then, that actions are treated as foreign entities throughout the literature on probability and statistics; they serve neither as arguments of probability expressions nor as events for conditioning such expressions. Even in the decision theoretic literature, where actions are the target of op-1Works by Dean & Kanazawa  and Kushmerick et al.  notwithstanding.
Jan-11-2006, 07:52:39 GMT